Exam 2
What is the median score for the following set of numbers? (3, 11, 8, 13, 5, 3, 6)
6
A correlation of .00 between two variables indicates
Independence (no association) between the variables
Which of the following correlation coefficients reflects the greatest linear relationship?
-.98
What is the mode(s) for the following set of numbers? (5, 10, 4, 1, 4, 5, 12, 8, 9, 4)
4
A null hypothesis is
A statistical hypothesis that assumes that there is no difference among the effects of treatments
The property of a distribution of scores that relates to how peaked or flat the curve is called
Kurtosis
Data such as gender, city of residence, or political party affiliation are what kind of measure?
Nominal
The term that describes the position of the hump in the curve of a distribution is
Skewness
A researcher finds a correlation of .70 between popularity ratings and self-concept scores. What percentage of common association can be inferred between the two variables?
49%
Another term for the mean
Average
If two measures have a high positive correlation, and a person has a low score on one measure, her score on the other measure is most likely to be
Low
Three of the following four things have something in common. Which does not belong with the other three
Mean
Which hypothesis is stated in the null form?
There is no significant difference between the vocabulary scores of average and high ability students.
Reliability of a measure may be established by
A and b only
If a correlation coefficient of 1.15 is found, this would indicate
A computational error
When the purpose of the research is to determine the effects of one independent variable (e.g., four groups) on one dependent variable (e.g., self-concept), the best choice of a statistical analysis is
Analysis of variance
A statistical technique that test for significant differences between observed and expected frequencies of occurrence is
Chi square
Comparing test items with the course objectives (course topic) checks which type of validity?
Content
Prediction studies use which of the following as the basic analysis technique?
Correlation
A measure of meaningfulness that expresses the difference between the experimental and control group in standard deviation units is the
Effect size
For a study with two (or more) independent variables, such as type of instruction and sex, and one dependent variable, such as achievement, the most appropriate analysis technique is
Factorial ANOVA
A threat to the validity of rating scales is that the rater may tend to let her previous knowledge of the student in another capacity influence the rating. This threat is called the...
Halo effect
A teacher wishes to determine the reliability of three trials on a performance test. He uses ANOVA to obtain the reliability coefficient. This technique is called
Intraclass correlation
Which of the following is not affected by the value of every score in the set on which it is calculated?
Median
If there is a correlation of .80 between a test of scholastic aptitude and performance on an achievement test, one can infer that
No causation can be inferred
In multiple regression, one is able to predict
One criterion from two or more predictors
Lining students up according to height without actually measuring height represents what level of measurement
Ordinal
A thermometer measured the temperature in an oven as 400° five days in a row when the temperature was actually 337°, this measuring instrument would be considered
Reliable but not valid
If a researcher finds a small difference in average test scores between large sample (over 700) of experimental participants and a large sample (same size) of control participants, it is very likely that the difference is
Statistically significant but does not have a high degree of meaningfulness
Four skills tests are tried as predictors of success in a tennis class. Each test correlates with later success as follows; test A, R=.27; test B, r= -.90; test c, r= -.40; test D, r= .65. The test that will most accurately predict success is...
Test b
If there is a negative relationship between two physical measure,
The value of one measure increases as the value of the other measure decreases
The correlation between X and Y is .90. What can be said with certainty about y in relation to X?
They are related
Why are standard scores so important?
They permit scores to be compared more appropriately
The sum of the deviation scores from the mean will always be zero
True
If the researcher fails to reject the null hypothesis when there really is a difference, this is an example of a
Type II error
When a researcher states that a result is significant, this means that:
the result is unlikely to be a chance occurrence
If ANOVA has found a significant different among four treatment groups, a post-hoc analysis is needed to determine
which of the groups differ significantly from the others
Between what limits can the Pearson product moment coefficient of correlation vary?
-1.0 and +1.0
The shape of a scatterplot you would expect between the shoe size and performance in a graduate statistics class would resemble
An orange
A main disadvantage of nonparametric techniques that has frequently been stated (although there is some disagreement)
Are not as powerful (less likely to detect a false null hypothesis) as parametric technique
The accuracy with which a 12-min run estimates maximal oxygen consumption in a group of male high school seniors represents
Concurrent validity
How does one describe a distribution that has many more high scores than low scores?
Negatively skewed
In order to make statements such as 8 units is twice as much as 4 units, what level of measurement is required
Ratio
Oxygen uptake capacity measured in liters per minute is an example of which type of measurement?
Ratio scale measurement
The standard deviation represents the
Spread of scores about the mean
Which of the following is a characteristic of ratio scale measures?
They have a real zero value
A physical education teacher develops a skill test in volleyball. After administering the test to 50 students, she asks the volleyball coach to rate the students on volleyball skills. She then correlates the students' test scores with the coach's rating. This is an example of what type of validity?
criterion validity
To determine whether data are normally distributed, one can test to see whether the curve is shifted to the left or right. This shift is called
Skewness
Which of the following is a characteristic of ordinal scale measures?
They indicate rank order
Validity is determined by finding the correlation between scores on
a test and some independent criterion